Dragons (Chinese: long) are a potent and prominent symbol in Chinese culture. The origin of the dragon image is unknown because it is so ancient. However, it is not unreasonable to assume that some of the massive fossilized bones encountered in several parts of China, including dinosaur and mammoth bones, were thought by ancient people to be those of huge dragons.

Dragon bones (longgu) and dragon teeth (longchi) were recorded in the Shennong Bencao Jing (ca. 100 A.D.) and were especially valued for their treatment of spirit disorders (1):

Dragon bone is sweet and balanced. It mainly treats heart and abdominal demonic influx, spiritual miasma, and old ghosts; it also treats cough and counterflow of qi, diarrhea and dysentery with pus and blood, vaginal discharge, hardness and binding in the abdomen, and fright epilepsy in children. Dragon teeth mainly treats epilepsy, madness, manic running about, binding qi below the heart, inability to catch one's breath, and various kinds of spasms. It kills spiritual disrupters. Protracted taking may make the body light, enable one to communicate with the spirit light, and lengthen one's life span.

Dragon bone, usually combined with oyster shell (muli), figured prominently in the Shanghan Lun and companion text Jingui Yaolue (220 A.D.), particularly in the sedative formulas Cinnamon and Dragon Bone Combination (Guizhi Jia Longgu Muli Tang) and Bupleurum and Dragon Bone Combination (Chaihu Jia Longgu Muli Tang), the latter being widely used today. Another formula with dragon bone and oyster shell that is still popular today is the Pill of Golden Lock (Jinsuo Gujing Wan), from Yifang Jijie (1682).

That the bones were still attributed to dragons for a long time is indicated by an illustration (see Figure 5) in the Bencao Pinhui Jingyao written at the beginning of the 16th century (2). It was not until after 1950 that investigations began into the true nature of these "dragon" parts (3-5). They were found to be mainly the fossilized bones and teeth of various mammals: some of them extinct animals others of modern species. Most of the fossils were likely formed during the latter part of the ice age period (about 20,000 to 12,000 years ago).

Dragon bone and tooth materials were obtained from the market place and analyzed by several Chinese institutes. The researchers were not able to assuredly identify most of the materials, but the following have been found:

Rhinos: mainly the long extinct rhino species, that were large, wooly, and had long double horns.

Hipparion: an ancient three-toed horse; additionally, bones and teeth of early camels are found.

Gazella: Gazelle were prevalent at the end of the ice age, hunted by humans. Other animals, such as mountain goats and sheep, deer, and buffalo also contribute to the fossil materials.

About 18,000 years ago, the mammalian wildlife, with many large and wooly animals, was especially prevalent in the zone between the glacial masses to the north, and the warmer regions to the south. The map below illustrates this zone of dense animal life in the central shaded region (labeled "mammoth"). It has been estimated that 10 million mammoth skeletons are buried under the Siberian tundra to the north of China. The southern portion of this mammoth range, within China, corresponds to the place where dragon bone and dragon teeth are found in largest quantities. There are likely millions of these remains within Chinese borders.

There are two basic groups of dragon bone on the market; one is called either tu (local), fen (powdery), or bai (white) dragon bone; the other is called hua (variegated, flowery) dragon bone, the latter often presented wrapped tightly in paper. Bailonggu is characterized as very solid, being difficult to break, and showing no vein-like lines, just a pale color and somewhat powdery surface. Hualonggu is considered the higher quality material; it is easier to break, and has many vein-like lines of various colors (such as red, blue, yellow, and brown on a gray background). Dragon teeth are naturally present in much lower quantities; they are mostly long narrow canine and shorter wide molar teeth. The best quality dragon teeth are those that have dark veins and that readily absorbs moisture. The main source of dragon bone and dragon teeth is Shanxi, but they are also collected in the adjacent areas of Inner Mongolia (as far west as Gansu, next to Inner Mongolia), Shaanxi, and Hebei (see map below). The higher quality bones tend to be found to the west and south, such as in Qinghai, Sichuan, Yunnan and Guangqxi provinces. Official permission from the Chinese government is required for collection of fossil bones, to avoid having collections from important paleontology sites.

Both dragon bone and dragon tooth are supplied by pharmacies in two forms: raw (sheng longgu) and calcined (duan longgu). Calcining is carried out by heating the fossil until it turns red, in a low oxygen atmosphere. The raw materials are deemed suitable for treating convulsions, as in epilepsy. For the bone, calcining is undertaken to make the material more suited for use as an astringent, such as to treat vaginal discharge, diarrhea, or night sweating. For the teeth, the calcining is used to focus the effect on treatment of insomnia and night sweats. Raw bone and teeth have a cool nature; with calcining, they have a neutral nature.

The main constituents in dragon bone and dragon teeth are calcium carbonate and calcium phosphate. They also contain small amounts of iron, aluminum, silicate, sodium and potassium chloride, and traces of manganese, magnesium, titanium (6). The colors in the hualonggu are attributable to some of the trace elements; its rating as being of higher quality may reflect the nutritional and therapeutic value of those elements. A concern was raised that these mineralized remains might contain toxic heavy metals (7), but this turned out not to be the case.

When cooking the materials in decoction, only a small amount is extracted. To enhance the extraction, the material is first crushed to powder and then boiled for a prolonged period (as is oyster shell and other mineralized materials), even before the other ingredients of the formula are added. Still, the dose in decoction is typically 15-30 grams for a one day supply. From a nutritional standpoint, this amount may yield significant levels of calcium for those who suffer from calcium deficiency. The calcium content of the material is on the order of 33%, and if as much as 10% of that can be extracted into the decoction, the tea will yield about 500-1,000 mg of calcium (based on 15-30 grams). These are the amounts of calcium typically recommended, as modern supplements, for adults who have deficient levels from their diet. In China, milk and milk products were absent from the diet, so that low calcium intake was very often a problem.

Samples of dragon tooth (top) and dragon bone (bottom) of the variegated type. Whole pieces are often much bigger and are broken up to be used in the pharmacy, where they are then often crushed to make powder.

Dragon bone is classified as sweet, astringent, and mild in nature. It is taken internally to tranquilize nervousness, calm the mind, and astringe sweating; topically it is used to promote tissue regeneration and astringe boils. In modern Chinese clinical practice, dragon bone is most frequently used to "settle uprising yang." This syndrome can contribute to hypertension, stroke, menopausal hot flashes, and various mental disorders. Dragon tooth is classified as astringent and cool. It is taken to stop palpitation, calm the mind, clear away fever accompanied by restlessness, and treat epilepsy. Dragon bone and tooth materials are not recommended for use in cases of heat accumulation due to excess-syndrome. Yang Yifan explained the differentiation of dragon bone and dragon tooth this way (8): "Dragon tooth is heavier than dragon bone and its descending property is stronger and quicker than that of dragon bone. Dragon tooth is very effective for sedating the heart spirit and calming the mind and is used to treat manic-depressive psychosis, hysteria, anxiety, irritability, and insomnia. Dragon bone has two functions that dragon tooth does not. First, it can anchor the liver yang to treat liver yang rising, which manifests as dizziness, tinnitus, headache, and dream-disturbed sleep. Second, it can stabilize the leakage of the essence and body fluids."